Valve-grinding device



F. R. WHITCOMB.

VALVE GRINDING DEVICE. APPLICATION FILED MAY 16, 1919.

Patented June 7, 1921 2 SHEET SHEET 1.

F. RfWHITCOMBL VALVE GRINDING DEVICE.

APPLICATION FILED MAY 16, I919.

Patented June 7, 1921.

2 SHEETS-SHEET 2.

Z72 Vania 7": fires Z ZJAZZEOmZ whit-TE FORREST R. WHITCOMB, OF WEST SOMEB-VILLE, MASSACHUSETTS.

VALVE-GRINDING DEVICE.

T 0 all whom it may concern:

Be it known that I, Fonmsr R. WHIT- COMB, a citizen of the United States, and resident of West Somerville, county of MiddleseX, Commonwealth of Massachusetts, have invented an Improvement in Valve- Grinding Devices, of which the following description, in connection with the accompanying drawings, is a specification, like characters on the drawings representing like parts in each of the several views.

This invention relates to apparatus for grinding and refitting valves to their seats by means of a tool that is constantly oscillated and at the same time advanced unidirectionally so that the range of oscillation is constantly shifted and an even and true refitting of the valve to its seat thus insured. One important object of the invention is to provide a device of this kind including gear elements and connections for constantly advancing the tool unidirectionally that is self-locking so that the tool is held secure with respect to its oscillating driving connection at each movement thereof without any separate provision for attaining this end. A further object is to provide a tool of the kind described with a crank connection for oscillating the same arranged so that the drive imparted to the oscillated tool is in harmonic relation to the driving member and whereby the rate of movement of the tool is gradually slowed down at the end of each stroke so that the shock is minimized and the device thus better adapted for use as a hand tool. A further object is to provide a tool for the purpose stated, equipped with operating gearing of the simplest possible form for producing the required movements, this being a feature ofgreat importance, since it permits the tool to be made light enough so that it may conveniently be employed as a hand tool; the present construction permitting the entire tool with its housing to be produced in a standard size, weighing only about three pounds, or less than half the wei ht of similar tools now in common use.

A further advantage of the present construction is that the operating crank may be rotated in either direction or oscillated for part rotations, in either case imparting the same operative movements to the tool bit,- this being? a feature of importance where it Specification of Letters Latent. Pat t d June I 19121 Application filed May 16, 1919. 1

Serial No. 297,661.

is necessary to use the tool in corners and other restricted spaces.

The foregoing and other objects and advantages of the invention will more fully appear from the following detailed description, and the distinctive features of novelty will be pointed out in the appended claims.

Referring to the drawings:

Figure 1 is a vertical section of a device embodying the invention, the operatin ele ments being shown in elevation; is

F ig. 2 is a sectional detail showing the immediate operating gearing;

Fig. 3 1s a sectional plan view on line of Fig. 2; I

Fig. a is a partial sectional elevation similar to 1g. 1, but showing the moving parts in a different position; and

F 5 is a partial sectional elevation looking from the right in Fig. 4 and with the driving gears and crank connection omitted, b1

$111133. ehousin 10 is e ui ed with bearings 11, 12 at the? respectii e d n ds thereof to receive a shaft 13 which is fitted to turn therein. These bearings are illustratively shown as of the ball-bearing type with the balls 11 thereof held in suitable cages 11*, which are detachably threaded into the housing. The housing is also shown as equipped with a suitable handle 14: at the rear end thereof, whereby the device may serve as a hand tool to be held against the work. The shaft 13' is equipped at'an outer pro ect1ng end thereof with a tool socket 15 in which is fitted a suitable tool for engaging thevalve or the like to be turned, this tool being illustratively shown as an ordinary b11716. The intermediate portion of the shaft 13 within the housing has fittedto turn thereon an elongated sleeve 17 which rests at its lower end against the bearing shoulder 18 of the shaft, while its upper end has a bearing fit against a worm wheel 19 which is suitably fixed to the shaft as by means of a cotter pin 19*. The upper end of the sleeve 17 is equipped with a bearing bracket 20 rigid therewith, this bracket having spaced apart lugs 20 20 in which are journaled bearing studs at the extremities of a worm 21, which is fitted between said lugs, this worm being thus held in position to en-' gage the worm wheel 19. The bearing stud at one end of the worm 21 is extended outthrough the lug 20 and has fixed on the end thereof a ratchet wheel 22. This ratchet wheel is engageable by the upper end 23 of an endwise moving pawl 23, the lower end of this pawl being pivoted at 23 to a short crank arm 24: that is pivoted at 25 to the sleeve 17 this crank arm being rigid with a longer yoke arm 26, the forked inner extremities of which extend at either side of the sleeve 17 and are pivoted to pivot studs 25 carried thereby and extending at each side thereof. The yoke arm 26 has its outer extremity formed as a bearing stud 27 which is pivotally engaged by an arm 28 extending diagonally from a sleeve 29 which is rigid with a pinion 30, this sleeve and pin ion being journaled on pivot stud 31 set into a boss 32 of the housing. The arm 28 as shown extends at a 4-5 angle from its pivot stud 31 and since it is pivotally journaled on the stud 27 it holds this stud to turn with an orbital movement that is harmonic in character with this pivot stud also always held diagonal with respect to its axis of turning about the studs 25. The pinion is operatively engaged by a wheel 33 which is fixed at the inner end of a short shaft 3 ljournaled in a bearing stud 35 of the housing. The outer end of this shaft is equipped with a suitable operating crank 36, this being merely illustrative and intended to typify any suitable driving connection either manual or otherwise. The pawl 23 has its upper portion guided in an extension 20 of the bracket 20 and its operative end 23 is held engaged with the ratchet wheel 22 by a light spring 37 housed in said bracket extension. To prevent the ratchet wheel 22 from bein frictionally drawn backward by the engagement of the pawl, I provide a dog 33 pivoted to the bracket 20 and equipped with a light coil spring 38 which keeps it constantly engaged with the ratchet wheel.

Tn operation power is transmitted from the crank 36 or other external connection through the gears 33, 30 to the diagonal crank arm 28, the turning of which oscillates the sleeve 17 with a harmonic movement with respect to its driving connection, this resulting from the fact that the operative movement of the diagonal crank28 is taken up by the yoke arm 26 partly as an oscillatory impulse on the sleeve 17 and partly as a vertical swinging movement of said yoke arm about the pivot stud 25. Thus the shaft 13 with the tool is oscillated with a movement that gradually slows down toward the end thereof in each direction and vibratory shock on the hand of the operator holding the tool is reduced to a minimum. The engagement of the worm 21 with the wormwheel 19 looks the worm wheel to the sleeve so that it partakes of the oscillatory movement thereof, while the worm receives a stepby-step unidirectional movement under the parts also makes it much easier to operate and thus further adapts it for use as a hand tool. Instead of turning the crank 36 for complete revolutions, it may if required by reason of restricted space or otherwise be oscillated, and the tool spindle 13 will be oscillated and advanced in the same way, only providing the range of movement of the crank or driving element is sufficient to drop the pawl 23 back far enough at each movement to engage a new ratchet teeth. I am aware that the invention may be embodied in other specific forms. without departing from the spirit or essential attributes thereof, and I therefore desire the present embodiment to be considered in all respects as illustrative and not restrictive, reference being had to the appended claims rather than to the foregoing description to indicate the scope of the invention.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A device of the kind described, comprising a tool spindle mounted for rotation, means for oscillating said spindle, and means for progressively advancing said spindle unidirectionally during the oscillation thereof while retaining it in the same longitudinal position throughout, having gear elements through which the oscillatory move- -ment is transmitted constructed and arranged so as to be self-locking for the transmission of such oscillatory movement.

2. A device of the kind described, comprising a tool spindle mounted for rotation, means for oscillating said spindle, and means associated with said oscillating means for progressively advancing said spindle unidirectionally while retaining it in the same longitudinal position throughout, consisting in a gear element secured to said spindle, and another gear element engaged therewith equipped to receive movement from said oscillating means, said gear elements constructed and arranged so as to be self-locking for the transmission of oscillatory movement.

3. A deviceof the'kind described, com prising a tool spindle mounted for rotation and held from endwise movement, a sleeve loosely fitted to said spindle, a worm wheel fixed to said spindle, means for oscillating said sleeve, a worm carried by said sleeve engaging said worm wheel, and means for unidirectionally moving said worm connected for actuation by said sleeve oscillating means.

4L. A device of the kind described, comprising a tool spindle mounted for rotation, means for oscillating said spindle, and means for unidirectionally advancing said spindle step-by-step including a worm wheel and .fixed on said spindle, a worm carried by said sleeve and engaging said worm wheel, and a pawl and ratchet device for unidirectionally advancing said worm connected for actuation by said sleeve oscillating means.

6. A device of the kind described, comprising a tool spindle mounted for oscillation and held from endwise movement, unidirectional driving means'therefor, and con nections between said driving means and said spindle constructed and arranged to translate the unidirectional movement of said driving means into harmonic oscillatory movement of said spindle.

7. A device of the kind described, comprising a tool spindle mounted for oscillation and held from endwise movement, unidirectional driving means therefor including a crank arm pivoted on an axis transverse of said spindle and extending diagonally therefrom, and an arm tranversely pivoted to said spindle and having the free end thereof pivotally engaged with said diagonal arm.

8. A device of the kind described, comprising a tool spindle mounted for oscillation and held from endwise movement, unidirectional driving means therefor including a crank arm pivoted on an axis transverse of said spindle and extending diagonally therefrom, an arm transversely pivoted'to said spindle and having the free end thereof pivotally engaged with said diagonal arm, and means for unidirectionally advancing said spindle step-by-step during the oscillation thereof.

In testimony whereof, I have signed my name to this specification.

FORREST R. VVHITOOMB. 

